McDonald's spokesman Walt Riker said that common sense had prevailed in the suit. "We said from the beginning that this was a frivolous lawsuit. Today's ruling confirms that fact."

Although he dismissed the suit, Judge Robert Sweet granted the plaintiffs the option of filing an amended complaint within 30 days addressing the problems that Sweet found in the plaintiffs' original arguments.

Sweet said some of the arguments could be compelling if addressed in more depth, including the allegation that the processing of McDonald's food makes it more dangerous than a customer would have reason to expect.

"If plaintiffs were able to flesh out this argument in an amended complaint, it may establish that the dangers of McDonald's products were not commonly well known and thus that McDonald's had a duty towards its customers," Sweet wrote.

In the current suit, he said, no such hidden dangers are shown.

"Where should the line be drawn between an individual's own responsibility to take care of herself and society's responsibility to ensure others shield her? The complaint fails to allege the McDonald's products consumed by the plaintiffs were dangerous in any way other than that which was open and obvious to a reasonable consumer," Sweet said in his ruling.

Samuel Hirsch, the plaintiff's attorney, remained defiant. In a written statement his law firm said, "the plaintiffs are very pleased with the decision and have every intention of amending their complaint and refiling it in the federal court in the next 30 days."

"Contrary to what many may think," said Hirsch in a telephone interview with CNN, "we are not looking to get rich from a large money settlement. We are proposing a fund that will educate children about the nutritional facts and contents of McDonald's food."

"Every responsible person understands what is in products such as hamburgers and fries, as well as the consequence to one's waistline, and potentially to one's health, of excessively eating those foods over a prolonged period of time," said the food chain's lawyers.

In August, a suit filed by the parents of two girls claimed that McDonald's and two of its restaurants in the Bronx failed to disclose clearly and conspicuously the ingredients and effects of its food, much of which is high in fat, salt, sugar and cholesterol.

The plaintiffs argued that McDonald's should therefore be held accountable for the girls' obesity, heart disease, diabetes, high blood pressure, and elevated cholesterol.

Bradley said that a McMuffin for breakfast and a Big Mac meal for dinner was her regular diet. Pelman preferred the Happy Meals and used to eat at McDonald's three or four times a week.

Bradley's father, Israel, said he never saw anything in the Bronx restaurants that informed him of the food's ingredients. "I always believed McDonald's was healthy for my children," he said in an affidavit.

Samuel Hirsch, the lawyer bringing the case, called McDonald's food "physically or psychologically addictive." Hirsch accused the company of deliberately withholding information and targeting children. The effects of its food on people's health were "a very insipid, toxic kind of thing," Hirsch said.

Hirsch also was critical of McDonald's billion-dollar advertising campaign. "Young individuals are not in a position to make a choice after the onslaught of advertising and promotions," Hirsch contended.

McDonald's lawyers added it would be impossible to establish whether eating at McDonald's was a major cause of the girls' ailments. Genetics, medical conditions and sedentary lifestyles could also be factors, they said.

Judge Sweet's ruling dampens the hopes of fellow New Yorker Caesar Barber. Barber, 56, filed a suit in July against McDonald's, Wendy's, Kentucky Fried Chicken and Burger King. The 272-pound Bronx resident alleged that their food caused his obesity, two heart attacks and diabetes.

A McDonald's spokesman in the United States told CNN in a telephone interview that "this is one person's opinion. Eating McDonald's food can easily fit into a balanced diet. I eat its food every day and I'm perfectly healthy."